Tube cleaning device



C. P. CROFT TUBE CLEANING DEVICE March 11, 1958 Filed Jan. 11. 1957 3Sheets-Sheet l T Y .1111}. 1k F M. .F M E m1 Q un QM, mm M...1%....1lliiiiiiiii mo m V n u -1 Q Is A L -K a: Q w M @w x 3m Q NM Nc. wfi wm a Q v QQQ Q NN m\ g Q \v Q n mm mm li. a NM MN hw N an m mm 3N. mm

March 11, 1958 C. P. CROFT TUBE CLEANING DEVICE 3 Sheets-Sheet 2 lllllllll March 11, 1958 Filed Jan. 11, 1957 TUBE CLEANING DEVICE 3 Sheets-Sheet s 206' 212 M314 h fl I N V EN TOR.

CHARLES P. CROFT ATTORNEYS more DEVICE Charles P. Crott, Hagerstown,Md.,-'a'ssignor .to:.-lPan'gborn Corporation, Hagerstown, Md., acorporation of Maryland Applicationianuary 11 1, 1 95.7, .SerialEda-633,572

1f Claims- (CI. 51- 8) United State P t I.

pensive to manufacture and maintain to be commercially feasible, or they-'werenot capable of projecting the abrasive stream ithrough a tube ofany length with siifileient effectiveness "to thoroughly *cleantheinterior surface.

eaznotherzproblem of the prior mechanisms ofthis type wasfthe tendencyto develop so much pressureduring the blasting operation irthat thewalls of the tube became ruptured.

.In addition, .Lin those instances Where there are -a "batik of tubesstationarily positioned in vertical and horizontal relation to eachother, it is necessary tomove'the blasting means. both vertic'ally andhorizontally "-in order to operate ton all ithe .tubes. "Nothing'here'tofore developed has been capable of quickly "and easilyaccomplishingthis movement whilefimaintaining the e'lfieiency ofthebl-ast.

t It is','therefore, tone objectof the present invention to provide anabrasive blasting device which is "capable of thoroughly, quickly :andtetficiently cleaning' the interior of--.tubular;elernents.

:Another object 40f 'the :present invention is to provide an abrasiveblasting device which can be *quidk-ly and easily :moved to "a varietyin operative position-s relative to :diiierently :pos'itione'dtubular'elem'ents.

zAnother so'bjectxof [the present invention is to provide an abrasiveiblasting idevic'e lwliichautomatically operates to prevent" the buildup10f ipressure within the tubular elements being blasted to points Whereirupture-o'fthe tubular WaIiSiOCCUI'S.

' Other objects a and many of :the attendantadvantages :of thisinvention will bereadilyapprecizited ras'rthe same Lbecomes betterunderstood by reference to the-following detailed description whenconsidered in connection with the accompanying drawings wherein:

' Fig. l is a side levational view:of -an-apparatus embodying thepresen'tinvention;

Fig. 2 is an enlarged, detailed side view, partly .in section "andpartly in elevation, Jdf the blasting .nozzle assembly showninFigi 1;

Fig. 3v is.a front elevational view of amodifiedform o'f apparatusembodying the present invention;

Fig. 5 -is a somewhat diagrammatic "view showing-the basic elements ofthe fluid pressure system used'in"conjunction witntlie "apparatus o'fFigs. ,j3fa1fd4 and showing was ice

fig. 6 is an enlarged, detailed 1GP :Plan view pith: pump assemblyillustrated in'Figl'S,

Referring now in greater detail to the various figures of the drawingswherein similar reference characters refer to similar parts, there isillustrated in Figs. 1'and.i2, a blasting nozzle assembly, generallydesignated 10. nozzle assembly comprises a base 12 on which clamps 14hold a cylinder 16. Positioned for longitudinal .movement *withinythe"cylinder 16 is a piston 18 having a stem 20'extending out of theforward end of the cylinder.

"conduit 22 is connected, through a valve 23,10 one end of thecylinder,and a conduit 24 is .connected'through ava'1ve1'25 to theother endof'the cylinder. These conduits each connect with th'eJinIBIiOr of'thecylinder 16 at one of 'their ends and with a 'selectorvalve 26 .at other"ends. Thevalve 26 is preferably an ordinary type of 'four 'way valvewhich :may bemoved into alternative positions to 'open either one of thecon-duits'22 or 24 to the pressure fiuid, While keeping "the otherconduit open to atmosphere. This 'valve may be manually operated or maybe electrically operated, as by means of .a solenoidor the like. Thevalves 23'and 25'maybe adjusted to vary the speed of movement. of thepiston...in .the cylinder.

Leadin from the'valve "26 is a'conduit'ZS. This conduit"28-leads"toasource of fluid pressure. (notrshown'). However, interposed in thisconduit 28, between *the valve Z G and-the source 'of fluid pressure, is'a "pressureeregnlating valve, generally =illustrated 'at '"30, and apressure gauge 31. The valve 303is set to "deliver pressure "fluid, at apredetermined pressure, to the "cylinder 1'6. The pressure" setting isdeterminedby the crosss'sectional area of the tube being cleaned and bythe "resistance this .area would have to'the pressure of the =blaststream in the event -the tube iis completely blocked. The *fiuidpressure is set to hold 'the piston 18, upon which is mounted a nozzle32, against slightly less pressure than .woulWbe generated by' theaction of'the blast stream "in the blodiced tube. The pressure withinthe tube bing greaterpfl'l'e regulated-pressure fluid within thecylinder-"then acts to compress slightly to allow the piston to retractand relieve the pressure within-the tube. As soon as the blockage Withinthe tube has been removed *by blast action; the regulated pressure'fiuidforces the piston'o'utagain to sezil the nozzle tip againstthe tubeopening.

T he nozzle 3'2 comprises a housing 3 t-havinga-threaded bore *at 'oneend to threadedly receive the externallythreaded end 36 of the piston18. A lock nut 581101118 the housing 'on the threaded end oi-the"pistong'and between this lock'nu't 'andthe forward end'o'f thecylinder-1'6 is'provided a bellows seal'40, which permits movement ofthe piston relative to -the*'cylinder 'while maintaining the :cylindersealed ofi from the "atmosphere.

EWi'thimtheh'ousing 3'4 is provided an=lbow type,=curved passage 42,defined at its upper, vertical end' by aninternally-threaded nipple 44,and at its lower, horizontal end i by an internally-threaded nipple 46.Engaged'within the nipple 46 is :oneexternally-threadedcendtoftheitubular sleeve 48,vtheopposite:threadedend of-.which:is;engaged within tan internallythreaded connterbore :50 of 2a nozzle head '52 having anozzle passage 54therein. gasket v56 is positioned between :t-hetend lot -.t-he.-s1eeve48 and the internal end .of the -counterbore 5.0.

The .nipple 44 is adapted .to receive...an externally: threaded bushing58 having .an externally knurled -adaptor portion 60 extendingtherefrom. .Ihis ..,adaptor 60 frictionally engages within. the end ofan abrasive supply hose *62. This hose '62 is connected, atits otherend,'to amanifold 6'4, whichis, intum, connected tofthe' outlerendofa'pump 66. Also connected "to the manifold "6 31s a pipe 68 whichis, in'turn, :connectedlthroug'h,

" a pipefifl to a source of liquid "such as water or the like.

. 3' A pressure gauge assembly supply line.

The pump 66 is of the standard, power-operated type and is driven from amotor, not shown, through a .belt system connected to pulley 74. Atapered connector 76, having upper and lower flanges 78 and 80, connectsthe interior of the pump to a source of abrasive particles 82 through aconduit 84. The flanges 78 and 80 of the connector are attached tocorresponding flanges 86 and 88 on the conduit and pump openingrespectively, by means of clamps, bolts, screws, or the like. A sealinggasket is provided between each pair of mating flanges, as at 90 and 72is connected into the liquid 92. A similar construction is provided atthe outlet end of the pump, as shown at 94. The pump, itself, issupported on a base 96.

In operation, when a tubular workpiece, such as shown at 98, is to beinternally cleaned, the workpiece is placed in position, and the valve26 is operated to move the head 52 of the nozzle 32 against the adjacentopening of the tube. The pump is then operated to supply a mixture ofabrasive from hose 62 and of liquid from pipe 68 to the nozzle whichejects the mixture into the interior of the tube. If, during thisoperation, the pressure within the tube being cleaned exceeds apredetermined maximum, the valve 30 acts to automatically relieve thispressure in the manner described above.

In Figs. 3, 4, 5, and 6 there is shown a modified form of the inventionwherein the nozzle, instead of being stationary is arranged forsubstantially universal movement. This is accomplished by positioningthe nozzle assembly, generally indicated at 100, which is substantiallyidentical to that shown at 10, on a carriage, generally indicated at102. This carriage is movable both horizontally and vertically, and can,therefore, be adjusted into any desired horizontal and vertical positionrelative to the objects being blasted.

The carriage 102 is mounted for vertical adjustment between a pair ofrails 104, each rail being positioned on a frame 106. A pair ofvertically-spaced rollers 108 are rotatably mounted on each side of thecarriage and ride upon their respective rails 104. A pair of thrustrollers 110 extend transversely to rollers 108 and bear against theframe 106 to provide moveable stability for the carriage.

A cable 112 is connected to the top of the carriage, as at 114 and, atits other end, the cable is connected to a winch 116 mounted on arotatable shaft 118 extending through the frame 104. The shaft 118 ispositioned be tween bearings 126 on the supporting framework 128. Thewinch 116 is splined to move back and forth on the shaft 118.

Mounted on one end of shaft 118 is a sprocket 130. A chain 132 connectssprocket 130 with a sprocket 133 mounted on a shaft 134 rotatablypositioned on the supporting framework. A hand wheel 136 is connected tothe shaft 134 to rotate the shaft and, thereby, by rotating the winch ineither direction, move the carriage 102 up or down, as desired.

In order to move the carriage horizontally, the upper portion 138 of theframe 106 is provided with upstanding brackets 140 supporting a rack bar142. The teeth of the rack bar are in engagement with a pinion 144mounted on a rotatable shaft 146 positioned within bearing members 150on either side of the framework 128. A guide 152 is mounted on framework128 and is positioned between oppositely disposed thrust rollers 154rotatably mounted on frame 106. A sprocket 156 is also provided on theshaft 146 and is connected by a chain 158 to a sprocket 160 mounted on arotatable shaft 162. This shaft 162 is positioned in bearing 164 on thesupporting framework and is provided with a pinion 166 which meshes witha rack 168 on the bottom of the frame 106.

Above the rack 168, the frame is provided with thrust rollers 170 whichabut against either side of a guide plate '4' 172 connected to thesupporting framework 128. The shaft 162 is journaled in a bearing member174 on the framework 128 and is provided, at its outer end, with a handwheel 176.

By means of the above-described apparatus, the handwheel 136 can beoperated to move the carriage 102 vertically on the frame 106 and thehand wheel 176 can be operated to move the entire frame 106horizontally.

The fluid circuit for the apparatus of Figs. 3 and 4 is illustrated inFigs. 5 and 6. In Fig. 5, the nozzle assembly .100 is shown positionedwithin a housing 178. The pump 180 is outside the housing and isconnected to the nozzle by a pipe 182 extending through the housing andconnected to a flexible hose 184. The compressed air or other fluidpressure medium for operating the nozzle-holding piston flows from asource of fluid pressure, not shown, through a pipe 186 which isconnected, within the housing, to a flexible hose 188. The hose 188 isconnected, through valve 190, to conduit 192 and 194 on opposite ends ofthe nozzle cylinder. A pressure-regulator valve 196, similar to valve30, is provided between the valve 190 and hose 188.

A pipe 198 connects an abrasive storage tank and separator, not shown,but of the type commonly used in the industry, to the valve 200; thepipe 198 being connected to that portion of the storage tank andseparator in which the reusable abrasive particles are collected. Acut-off valve 202 is interposed between the regulating valve 200 and thestorage tank and separator in order to cut off flow therefrom duringrepair or replacement of the valve 200. The valve 200 is used toregulate the proportion of reusable abrasive and fresh abrasive suppliedto the pump.

In connection with valve 200 is a pipe 204 leading from a source offresh abrasive material. The valve 200 is connected by a pipe 206 to atapered connector 208, similar to that shown at 76; this connector beingattached to the inlet opening of the pump. Also attached to theconnector 208 is a pipe 210 leading from a source of water, or otherdesirable liquid.

The pump 180 is driven by a motor 212 through a belt 214 connectedbetween variable pitch pulley 216 on the motor shaft and pulley 218 onthe pump shaft.

The apparatus illustrated in Figs. 3, 4, and 5 is especially suitablefor cleaning the interiors of the individual tubes in the so-called tubebundles commonly used in the oil industry and indicated at 220 in Fig.4. In these tube bundles, where the individual tubes are fixed inrelation to each other, it is necessary to move the nozzle from tube totube.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is, therefore, to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. A tube cleaning device comprising a base, a fluidpressure actuatedpiston operatively connected to said nozzle to move said nozzle relativeto said base and against one end of a hollow workpiece, a conduit forsupplying a fluid pressure medium to said piston, supply means to supplyan abrasive mixture under pressure to said nozzle for ejection by saidnozzle in an abrasive stream, and regulating means operative to retractsaid nozzle from said workpiece piston when the pressure within saidworkpiece exceeds a predetermined maximum value.

2. The device of claim 1 wherein said base is fixed.

3. The device of claim 1 wherein said base is mounted on a carriagewhich is movable both vertically and horizontally.

4. A tube cleaning device comprising a base, a cylinder on said base,inlet means on opposite ends of the cylinder, a piston in said cylinder,a nozzle for ejecting an abrasive stream under pressure connected tosaid piston externally of said cylinder, conduits connecting both ofsaid inlets to a selector valve, said selector valve being connected toa source of pressure fluid and being constructed and arranged toalternatively open each of said conduits to said pressure fluid whileopening the other to atmosphere, an abrasive-mixture supply lineconnecting said nozzle with a source of abrasive-mixture, and apressure-regulator valve interposed between said selector valve and saidsource of pressure fluid, said pressure-regulator valve being operativeto deliver said pressure fluid to said selector valve at a predeterminedpressure.

5. The device of claim 4 wherein an expansible sealing means connectssaid nozzle to said cylinder.

6. The device of claim 4 wherein said abrasive-mixture supply line isconnected to the outlet end of a pump, said pump being connected to asource of reusable abrasive particles emitted from said nozzle to effecta recycling of abrasive material through said nozzle.

7. A tube cleaning device comprising a support, a frame means movablymounted on said support for movement therein in one direction, acarriage means movably mounted on said frame means for movement thereinin a direction transverse to said first direction, an abrasive-blastingnozzle means movably mounted on said carriage for movement thereon in adirection transverse to said first two directions, and operating meansto selectively operate each of said other means.

8. A tube cleaning device comprising a support, a frame positioned onsaid support for horizontal movement relative thereto, said frame havinga rack in mesh with a pinion on said support, means to rotate saidpinion, first guide means on said support in coacting relationship withsecond guide means on said frame to guide said frame during itshorizontal movement, vertical guide structure on said frame, a carriagevertically movable along said guide structure, means to move saidcarriage along said guide structure, and a blasting nozzle on saidcarriage said nozzle being operatively connected to a source ofabrasive.

9. The device of claim 8 wherein said first guide means on said supportis a plate and wherein said second guide means on said frame are thrustrollers mounted on opposite sides of said plate and in abuttingrelationship thereto.

10. The device of claim 8 wherein a rack is provided at each of theupper and lower ends of said frame, each rack being in mesh with acorresponding pinion, there also being coacting guide means at each ofthe upper and lower ends of said frame.

11. The device of claim 8 wherein said guide structure on said framecomprises oppositely disposed pairs of rails, said carriage beingprovided with rollers movable along said rails, a winch rotatablymounted on said support, a cable connecting said winch to said carriage,and means to drive said winch in reverse directions.

References Cited in the file of this patent UNITED STATES PATENTS1,882,541 Billman Oct. 11, 1932 2,451,635 Schratt Oct. 19, 19482,611,219 Gladfelter Sept. 23, 1952 2,692,458 Lawrence Oct. 26, 1954

